Reamer



United States Patent Ofiice 3,051,255 REAMER Carroll L. Deely, 6210 N. Central Expressway, Dallas, Tex. Filed May 18, 1960, Ser. No. 29,847 4 Claims. (Cl. 175265) This invention relates to bore hole reamers for use with rotary well drills and more particularly to an expansible bore hole reamer for reaming the bore hole being drilled by a rotary drill bit, such as a diamond bit or the like, as the bore hole of the well is being drilled. Furthermore, the present reamer is so constructed that, when placed directly above a drill bit, it reams the bore hole of the well and stabilizes the drill bit as the well is being drilled, so as to drill a straight, concentric hole, and to prevent spiraling of the hole.

Various reamers have been proposed heretofore, both of the expansible type and of the type for reaming the walls of the well after the well has been drilled; however, it requires additional time to ream a well after the drilling has been done, whereas with the present device, the Well is drilled and the bore hole reamed simultaneously with little or no added cost. The present reamer is so designed that, when the drill stem is going in the hole, the reamer blades are held in retracted position, wherein the greatest diameter through the reamer blades, when in retracted position, is of less diameter than the diameter of the drill bit. However, when the weight of the drill stem is placed upon the drill bit, the shear pins which hold the reamer blades in retracted position will be sheared, thereby permitting expansion of the reamer blades to a diameter greater than the diameter of the drill bit, whereupon, the bore hole is continuously reamed to a size larger than the diameter which the drill bit drills, and with these reamer blades only a few inches above the drill bit, the hole is maintained in condition so that the drill bit may be withdrawn at any time upon withdrawing the drill stem.

The present expansible bore hole reamer is so constructed that, as the drilling progresses, the bore hole is enlarged sufficiently to permit Withdrawal of the drill bit at any time from any depth, and which reamer is of sufiicient size to prevent the bore hole from growing smaller due to swelling of certain types of formation, which swelling frequently causes bits to become stuck, due to the decrease in the size of the bore hole above the bit, and therefore it is difiicult to remove a bit from a Well under such conditions.

An object of this invention is to provide a reamer for a bore hole, the blades of which reamer will be positively expanded when the Weight of the drill stem is placed thereon so as to ream the hole to a larger diameter than the diameter of the hole drilled by the bit.

Another object of the invention is to provide a bore hole reamer to be used with a drill bit, which reamer will continuously ream the bore hole of a Well being drilled by the rotary drilling method, to a size larger than the bore hole being cut by the drill bit, which reamer will simultaneously stabilize both the drill bit and the drill stem.

A further object of the invention is to provide a bore hole reamer for a drill bit which will pass through an opening smaller than an opening through which the drill bit will pass, such as the inside diameter of well casing, but which will expand therebelow to a size larger than the inside diameter of the well casing.

A still further object of the invention is to provide a bore hole reamer for use with a drill bit which will expand by the weight of the drill stem to ream simultaneously with the drilling operation of the drill bit, but

which will ream the bore hole to a size larger than the bore hole cut by the drill bit, thereby obviating the necessity of a separate reaming operation.

Yet another object of the invention is to provide a reamer which will eliminate sticking of the drill bit in formations, due to wall cake building up on the face of the bore hole because of mud loss in the formation.

With these objects in mind and others which will become manifest as the description proceeds, reference is to be had to the accompanying drawings in which like reference characters designate like parts in the several views thereof in which:

FIG. 1 is an elevational view showing a portion of a bore hole of a well with a drill stem, reamer, and a drill bit therein, with the drill stern and drill bit being shown in dot-dash outline, with portions of the reamer being bro-ken away and with portions shown in section to bring out the details of construction, with an alternate position of the reamer being shown in dashed outline;

FIG. 2 is a sectional view taken on the line 22 of FIG. 1, looking in the direction indicated by the arrows;

FIG. 3 is a sectional view taken on the line 33 of FIG. 1, looking in the direction indicated by the arrows;

FIG. 4 is a sectional view taken on the line 44 of FIG. 1, looking in the direction indicated by the arrows;

FIG. 5 is a sectional view taken on the line 55 of FIG. 1, looking in the direction indicated by the arrows;

FIG. 6 is a longitudinal, sectional view through the reamer with parts broken away and with parts shown in elevation.

With more detailed reference to the drawing, the m1 moral 1 designates generally the bore hole of a Well, with the numeral 2 designating the drilled size of the bore hole a screwthreaded connection on the lower end of drill,

stem 6. The body 12 has a circumferential groove 18 therearound a spaced distance. down from the upper end thereof, as will be particularly evident from FIGS. 1 and 6. A pair of complementary semi-cylindrical members 20 are fitted around the body 12 within circumferential groove 18, which semi-cylindrical members, when fitted together, have an outside diameter greater than the outside diameter of body 12. The semi-cylindrical members 20 are radially apertured, as indicated at 22, which radial apertures are adapted to register with radial apertures 24 within body 12, which apertures 24 are formed in the body at the lower portion of the groove 18. Shear pins 26 are adapted to pass through apertures 22 in the semicylindrical members 20 and into holes 24 in the body .12.

The shear pins have a calculated strength so as to holdthe shell 32 in fixed relation with respect to body 12 until it is desired to shear these pins 26, as will be brought out fully hereinafter.

The body 12 is splined immediately below the circumferential groove 18, as indicated at 28 as will best be seen in FIGS. 1, 3 and 6, which splined portion of the body is adapted to complementally receive a complementary spline 30 within sleve or shell portion 32 of the reamer 8. The shell 32 is exteriorly screwthreaded, as indicated at 34, at the upper end thereof to threadably receive a retainer collar 36, which retainer collar is adapted to telescope over the upper end of the reamer body 12 so that the counterbore 38 therein, will fit over. semi-cylindrical members 20 to hold the shear pins 26 Patented Aug. 28, 1962' in place to prevent outward radial movement thereof. The upper bore 4.0 of collar 36 is adapted to slidably receive the outside diameter of body 12.

An intermediate portion of the body 12, between the splined portion 28 and the lower end, has an exterior conical taper 42 formed thereon to complementally receive the inner faces of reamer blades 44. It is preferable to have a multiplicity of reamer blades 44 circumferen tially spaced around'the conical tapered portion 42 of body 12, four such blades having been shown in the present instance. The shell 32 has circumferentially spaced, longitudinally aligned slots 46 formed therein to complementally receive reamer blades 44 therethrough, which slots are of suflicient length to permit full outward movement of the reamer blades 44 when the body 12, with the conical, tapered portion 42 thereon, moves downward relative to the shell portion 32. However, the end portions of the slots 46 are formed at the same angle as the end portions of the reamer blades 44, so when the reamer is .fully extended, the blades will be allowed to project only a predetermined distance outward.

The lower end of the reamer body 12 has circumferential grooves formed therein to complementally receive sealing elements 50, which sealing elements 50 may be Q-rings or the like. These sealing elements form a complementary seal with a cylindrical bore 52 in the lower portion of shell 32. The shell 32 has an axial opening 54 therethrough for the passage of drilling fluid therethrough and through the axial opening 14 in the body 12.

The lower end of the shell 32 is screwthreaded, as indicated at 56, to threadably receive the upper end of drill bit 10, so that the drilling fluid passing through drill stem 6,, body 12 and shell 32 will pass into an axial opening (not shown) in drill bit 10, in a manner well understood in the art of well drilling. The sealing elements 50 form a fluid tight seal between the shell 32 and body 12 so the drilling fluid is directed from body 12 into shell 32 without leakage of drilling fluid thereby, either when in raised position, as shown in full outline in FIGS. 1' and 6, or when in telescoped position, as shown in ashe ou in n G- The innerfac es of reamer blades 44 are concave, so as to form complementary, interengaging faces to fit against the conical tapered portion 42 of the body 12. The outer faces of of the reamerblades 44 preferably have hard surfacing material 58 bonded thereto, so as to increase the resistance to wear, or if desired, the entire projectn n r n each amer "b a e 4 ma a rd rmaterial thereon.

With the body. 12 in raised position relative to shell 32, the semi-annular rings 20 engage an inturned shoulder on retainer collar 36 and an'outturned upper shoulder on bod 2 t imi e pward mo eme t of he bod-Y 12 elat ve qshe l 32-. When t e b dy- 12 is in the upp most position, anannular space 13 is formed between an outturned shoulder portion on body 12 below splines 28 and an .inturne'd shoulder formed on the intermediate portion of shell 32', however, upon downward movement of body 12 relative to shell 32, the complementary tapers on body 12 and shell 32 will engage to norrnally 'forrna stop before the last mentioned shoulders interengage. H V WIQ if wear should occur on the tapers of the body and the shell, or, if the shell should become unduly expanded, these last mentioned shoulders will form a positive stop between the body 12 and the shell 32. Upon relative movement downward between the tapered portion of body 12 and the shell 32, the reamer blades 44 are forced outwardly, however upon upward movement of the. tapered portion 42 of the body relative to shell 32, the lower tapered end portions of blades 44 will move along the tapered portions of slots 46 by gravity, or will move inward with the slightest pressure thereon so that the reamer blades will not engage the wall of the bore hole as the reamer is moved upward.

Operation When drilling deep wells in hard formation, it is desirable to use special rock cutting bits, such as three-cone milling cutter bits or diamond bits, or bits with hard surfacing material on the wear faces thereof, to retard the wear on the bits during the cutting of hard formations. It has been generally accepted by the industry, that bits with three contact faces out faster than comparable bits having either two or four contact faces. It has also been found that bits with three contact cutting faces do not drill a true concentric hole, especially when excessive weight is placed thereon, to obtain the maximum cutting performance. Furthermore, the bore cut by such a bit often attains the shape of a long spiral, therefore when a concentric pipe, such as casing, is run into the bore hole, it is often found that, at certain points in the hole, the casing will not pass, in which event, the hole has to be reamed to enable casing to be run thereinto.

With the use of the present reaming device, a drill bit with three cutting faces, such as a diamond bit or a three cone rock bit or the like may be used to cut the bore hole through the desired formation at a rapid rate. However, since the hole so drilled will probably not be concentric or cut to the desired size, the present reaming tool is installed immediately above the drill bit 10, and when lowered into the hole being drilled, 'the cutter blades are maintained in a retracted position, by shear pins 26 positioned through apertures 22 and through holes 24 in body 12, with collar 36 screw threaded into place to hold semi-cylindrical members 20 against relative movement, and with bit 10 screwed onto the lower end of the shell 32 of reamer 8, and with the upper end of body 12 of reamer 8 screwed onto the lower end of drill stem 6, the reamer is ready to be lowered into the bore hole until the drill bit contacts the bottom thereof. Upon continuing downward movement of the drill stem 6, shear pins 26 will be sheared and the body 12 of the reamer 8 will telescope into shell 32 thereof, from the position as shown in full outline in FIG. 1 to that shown in dashed outline therein, whereupon, the conical, tapered portion 42 of the body 12 will move downward between the reamer blades 44 to wedgingly move the reamer blades 44 positively outward to fully expand the reamer blades until the respective tapered ends thereof are moved into wedging engagement with the complementary tapered end portions of the respective slots 46 of shell 32, with the tapered end portions of the reamer blades 44 wedged into the respective complementary tapered end portions of slots 46. In this manner torque may be transmitted from dnil'l stem 6, through the shell 32 to the reamer blades 44, as the reamer blades are held in rigid relation with respect to the tapered portion 42 and sleeve 32, which will prevent back lash between the interengaging splines. With the tapered portion 42 of the body in the position described, when the reamer blades are fully expanded, the end surfaces thereof interengage the complementary tapered end portions of the slots 46, and with the reamer blades fully expanded, they have a transverse dimension greater than the greatest transverse dimension of bit 10. However, the lower ends of the reamer blades 44 are tapered slightly so that the transverse dimension at the lower end thereof will be less than the smallest diameter of the bore hole cut by bit 10, and with the face of the reamer blades tapering upwardly for approximately half the length thereof, the upper portion of the reamer blades will be substantially parallel with the axis of the reamer and will ream :the bore hole immediately above the drill bit as the bore is being cut thereby. A four blade reamer has been shown to ream the bore bole to a size larger than the bore which the bit 10 will cut. Furthermore, by reaming the hole with a four blade reamer, the bore will be substantially concentric.

In the drilling of wells using the reamer herein described, in conjunction with the drill bit, the well may be drilled and reamed to size in the same length of time and at approximately the same cost as the drilling can be done with a conventional drill bit.

With the reamer blades 44 fitted within slots 46 in the manner brought out above, the reamer blades 44 will not be lost during the drilling operation, since during this time, the reamer blades remain tightly wedged within sleeve 32 by tapered portions 42 of the body 12, throughout the drilling operation. However, upon the removal of collar 36 the tool may be readily disassembled to enable the removal of the reamer blades 44 and the replacement thereof in a minimum of time and with a minimum of effort. Furthermore, blades of one size may be removed and replaced with blades of a different size, thereby enabling the same reamer body 12 and sleeve 32 to be used for a number of different size reamer blades, thereby holding the cost of the tool to a minimum.

While the invention has been illustrated and described in some detail for one embodiment thereof, it is to be understood that changes may be made in the minor details of construction and adaptations made to different installations without departing from the spirit of the invention or the scope of the appended claims.

Having thus fully illustrated and described the invention, what is claimed as new and desired to be secured by Letters Patent is:

l. A tool for reaming the bore hole of a well, which tool is positioned above the drill bit and which reams the bore hole as the well is being drilled with a rotary drill bit, said tool being adapted to be positioned on the drill stern intermediate the lower end thereof and the drill bit, portions of which tool are expansible by the weight of the drill stem on said drill bit, said tool comprising; a body, said body having an axial opening formed therethrough, a portion of the surface of said body being convex and exteriorly tapered inwardly toward the distal.

end thereof, a hollow shell telescoped over at least the tapered portion of said body, at least a portion of said hollow shell being tapered to complementally fit said tapered portion of said body, means limiting the longitudinal movement of said body relative to said shell, means interconnecting said body and said shell in rotatable, driving relation, said shell having longitudinal slots formed therein, a reamer blade complementally fitted within each said slot in said shell and being rotatable with said shell, each blade having a concave side, which concave side complementally seats on the convex, tapered surface of said body throughout the entire length of each reamer blade, each said reamer blade being slidable relative to said tapered surface of said body, said reamer blades having the respective ends thereof converging in an outward direction with respect to the portion thereof which seats on said body, and the slots in said shell having the respective ends thereof converging in an outward direction in complementary relation to the ends of said reamer blades, the innermost length of each reamer blade being greater than the minimum length of said respective slots to retain the inner ends of said reamer blades within the respective slots in said shell.

2. A tool for reaming the bore hole of a well as the well is being drilled with a rotary drill bit, which tool is adapted to be secured to the lower end of the drill stem, a drill bit adapted to be attachably secured to the lower end of said tool, portions of which tool are expansible by the weight of the drill stem on said tool when the drill bit is on the bottom of the bore hole, said tool comprising; a body, said body having an axial opening formed therethrough, a portion of the surface of said body being convex and exteriorly tapered inwardly toward the distal end thereof, a hollow shell telescoped over at least a portion of said body, at least a portion of said hollow shell being tapered to complementally fit said tapered portion of said body, said shell having longitudinal slots formed therein, a reamer blade complementally fitted within each said slot in said shell and being rotatable with said shell, each blade having a concave side, which concave side of each blade complementally seats on the convex tapered surface of said body through the entire length of each said blade, each of which reamer blades is slidable relative to said tapered surface of said body, each said reamer blade having the respective ends thereof converging in an outward direction with respect to the portion thereof which seats on said body, the slots in said shell having the respective ends thereof converging in an outward direction in complementary relation to the ends of said reamer blades, the innermost length of each reamer blade being greater than the minimum length of each said slot so as to retain the inner ends of said reamer blades within the respective slots in said shell, an intermediate portion of said body above said tapered portion having splines formed thereon, a portion of said shell having splines formed therein, which splines interfit in complementary, sliding relation with the splines on said body to form a driving connection between said body and said shell, said body having a peripheral groove formed therein immediately adjacent said splined portion, semicylindrical ring members fitted within said peripheral groove, at least one of said semi-cylindrical ring members having a transverse aperture formed therein, said body having a radial recess formed therein in the bottom of said groove, which recess registers with said transverse aperture formed in one of said semi-cylindrical ring members when said body is in one position, a shear pin fitted in said aperture in at least one of said semi-cylindrical ring members, which shear pin extends into said recess in said body when said body is in one position, a threaded collar having a bore formed therein, which collar threadably engages said shell, said collar having a shoulder formed thereon in the bore thereof, which shoulder seats against said semi-cylindrical ring members when the shell is in one position with respect to said body, saidbore of said collar being adapted to telescopically receive said body, when said shear pin has been sheared, to limit the relative longitudinal movement of said body with respect to said shell.

3. A tool for reaming the bore hole of a well as the well is being drilled with a rotary drill bit, which tool is adapted to be secured to the lower end of the drill stern, a drill bit adapted to be attachably secured to the lower end of said tool, portions of which tool are ex pansible by the weight of the drill bit on said tool when the drill bit is on the bottom of the bore hole, said tool comprising; a body, said body having an axial opening formed therethrough, a portion of the surface of said body being convex and exteriorly tapered inwardly toward the distal end thereof, a hollow shell telescoped over at least a portion of said body, at least a portion of said hollow shell being tapered to complementally fit said tapered portion of said body, said shell having elongated, longitudinal slots formed therein, a reamer blade being complementally fitted within each of said slots in said shell, which blades are rotatable with said shell, each blade having a concave side, which concave side of said blade complementally seats on the convex tapered surface of said body throughout the entire length of each said blade, each of which reamer blades is slidable relative to said tapered surface of said body, each said reamer blade having the respective ends thereof converging in an outward direction with respect to the portion thereof which seats on said body, means intermediate said body and said shell to form a stop to limit the longitudinal movement of said body relative to said shell, the slots in said shell having the respective ends thererof converging in an outward direction in complementary relation to the ends of said reamer blades, the innermost length of each reamer blade being greater than the minimum length of each said slot to retain the inner ends of said reamer blades within the respective slots in said shell, an intermediate portion of said body above said tapered portion having 7 splines tormed thereon, .a portion of said shell having splines formed therein, which splines interfit in complementary, sliding relation with the splines on said body to form a driving connection between said body and said shell.

4. A tool for reaming the bore hole of a well as the well is being drilled with a rotary drill bit, which tool isadapted to be secured to the lower end of the drill stem, a drill: bit adapted to be attachably secured to the lower end of said tool, portions of which tool are expansible by the weight of the drill bit on said tool when the drill bit is on the bottom .of the bore hole, said tool comprising; a body, said body having an axial opening formed therethrough, a portion of the surface of said body being convex and exteriorly tapered inwardly toward the distal end thereof, a hollow shell telescoped over at least a portion of said body, at least a portion of said hollow shell being tapered to complementally fit said tapered portion of said'body, said shell having longitudinal slots formed therein, a reamer blade complementally fitted within each slotin said shell and being rotatable with said shell, each blade having a concave side, which concave side of said blade complementally seats on the convex tapered surface of said body throughout the entire length of each said blade, each said reamer blade being slidable relative to said tapered surface of said body, each said reamer blade having the respective ends thereof converging in an outward direction with respect to the portion thereof which seats on said body, the slots in said shell having therespective ends thereof converging in an outward direction in complementary relation to the ends of said reamer blades, the innermost length of each reamerblade being greater than the minimum length of each said slot to retain the inner ends of said reamer blades within the respective slots in said shell, an intermediate portion of said body above said tapered portion having splines formed thereon, a portion of said shell having splines formed therein, which splines interfit in complementary, sliding relation with the splines on said body to form a driving connection between said body and said shell, said body having a peripheral groove formed therein immediately adjacent said splined portion, semicylindrical ring members fitted within said peripheral groove, the depth of which groove is less than the thickness of said semi-cylindrical ring members, at least one of said semi-cylindrical ring members having a transverse aperture formed therein, said body having a radial recess formed therein in the bottom of said groove, which recess registers with said transverse aperture formed in one of said semi-cylindrical ring members when said body is in one position, a shear pin positioned in said aperture'in at least one of said semi-cylindrical ring members which shear pin extends into said recess in said body when said body is in one position, a threaded collar having a bore formed therein, which collar threadably engages said shell, which collar is counter-bored to form a shoulder therein, which shoulder seats against said semi-cylindrical ring members when the shell is in one position with respect to said body, said bore of said collar adapted to telescopically receive said body, when said shear pin has been sheared, to limit the relative longitudinal movement of said body with respect to said shell.

References Cited in the file of this patent UNITED STATES PATENTS u My 

